Process and agent for breaking petroleum emulsions



Patented Mar. 2, 1943 PROCESS AND AGENT FOR BREG PETROLEUM EMULSIONS Richard A. Salathiel, Houston, Tex., assignor to Standard Oil Development Company, a corporation of Delaware No Drawing. Original application October 19,

1938, Serial No. 235,781. Divided and this application December 19, 1939, Serial No. 309,956

14 Claims. (01. 252-342) This invention relates to a process for resolving water-in-oil emulsions and particularly to a new composition for the resolution of such emulsions.

This application is .a division of co-pending and its, esters, have the property of condensing through their unsaturated linkages with polycarboxylic unsaturated open chain acids and derivatives thereof in which the unsaturated 5 groupings are preserved. Most commonly this application Serial Number 235,781, filed October reaction is carried out with maleic acid or maleic 19, 1933. anhydride, or the corresponding fumaric com- Petroleum emulsions of the water-in-oil type pound. For the sake of simplicity, maleic ancomprise fine droplets of naturally occurring hydride and esters of maleic acid will be here- Waters or brines, dispersed in a more or less per- 9 inafter referred to for illustrative purposes, but manent state throughout t which tp it is to be understood that in such references the tutes the continuous phase of the emulsion. Whole r p t W c e e substances belong They are obtained from producing wells and is contemp ated. from the bottom of oil storage tanks, and are h are two st ps nt pr a a n of t s commonly referred to as but oil, roily oil, is treating nts. Th first is c densation y emulsified oil, and bottom settlings, the well known Diels-Alder diene reaction of a The object of the present invention is to prom f the r n aoid y w t a m l of maleic vide a novel and inexpensive process for sepaa hydr d to o a De y e d bedy- This rating emulsions of the character referred to condensation s ua y Carr ed out by heatin into their component parts of oil and water or go the a t R aet a y be at about brine, 100 C. but for a practical rate of reaction a v Briefly described, the present process consists temperature of the Order Of to in subjecting a petroleum emulsion of the watershould 2be p ye h upp limit On e in-oil type to the action of a treating agent or condensation temperature is that temperature demulsifying agent of the kind hereinafter d 5 at which the reactants decompose, and other scribed, thereby causing the emulsion to break detrimental reactions take P down and separate into its component parts of The second step is t e ac o of this po l!- oil and water or brine, when the emulsion is perbasic acid body to form suitable derivatives. mitted to remain in a quiescent state after treate p y asi ac d ody ay be m ned with ment, or is subjected to other equivalent sepa Water soluble bases, such s NaOH, NHIIOH, ratory procedures. methanol amine, etc., to form saltswhich have The treating agents used in this process efiective demulsifying powers for some emulsions. sist of derivatives oforganic, preferably alih po y acid y m y b e erified with phatic, unsaturated carbonyl compounds obmonohydric alcohols and with ether-alcohols to tained by the consideration therewith of resin yield materials that economically demulsify acids or resin acid bodies, some emulsions. The term ether-alcohol is used As used herein the term re in a id i us d t herein to designate an organic compound chardesignate abietic acid and pimaric, copaivic, acterized by the presence of bot a coholic palabietic, and other acids derived from the hydreXyl d e e O ygen (-0-), groups. oleo-resinous exudates from various species of Among suitable alcohols for the p rpose may be Coniferae which are either identical or isomeric mentioned mono-methyl, y 0 0- with abietic acid or are changed to abietic acid P DY monemutyl, y e hers of or an isomer of abietic. acid by heating. The ethylene glycol, diethylene ycol, triethylene term resin acid body is used to designate these ly ol, tetraethylene y p op l n g yacids or simple functional derivatives of these d5 blitylene glycol and o e yeo di-methy acids, such as salts, anhydrides and esters. Simdi-ethyl, di-propyl, di-butyl, etc., ethers of glycilarly, the term abietic acid body embraces salts, erol, and other tri-hydric alcohols; mono-alkyl esters, and the anhydride of abietic acid. ethers of tri-methylene glycol, tetra-methylene Typical of the unsaturated organic carbonyl glycol, penta-methylene glycol, and the lik A1 which may be employed are polycarboxylic un- 50 the polybasic' acid bodies may be condensed with saturatedopen chain acids, such as maleic acid poly ydric alcohols to yield materials having .and fumaric acid, their anhydrides and the corexcellent demulsifying powers. Typical of th responding aldehydes and ketones, :benzoquinone 'polyhydric alcohols which may be employed are and the like. ethylene glycol, diethylene glycol, triethylene Resin acid bodies, for example, abietic acid to ycolr tetraethylene glycol, propylene glycol,

mixed monohydric and polyhydric alcohol ester derivatives of the condensed polybasic acid body may be produced. Likewise, partially saponified complex ester derivatives of the resin acid bodymaleic anhydride condensation product may be highly eflicient demulsifying chemicals.

The order in which the reactions in the preparation of these derivatives are carried out is in most cases immaterial. A derivative of the condensed acid body may be prepared before or after condensation. For example, it is immaterial whether the mono-butyl ether of diethylene glycol is esterified with maleic acid and the resulting ester condensed with methyl abietate or the methyl abietate is first condensed with maleic anhydride and' the resulting condensation product esterified with the mono-butyl ether of diethylene glycol. It is the final product that it is desired to describe by the reactions set down. Reactions caried out in any other order to obtain these products must be regarded as equivalent.

The reagents preferred for use in practicing the process of the present invention are either the monohydric or the polyhydric alcohol este'r derivatives of the acid resin obtained by condensing an abietic acid body with maleic anhydride.

Specific illustrations of the products of thetype hereinbefore generally described which are suitable for use in accordance with the present invention are set forth below. It is to be understood that the present invention is not in any way restricted to the specific chemicals described in these examples or the proportions in which Methyl abietate, 316 parts, and maleic anhydride, 98 parts, are condensed together by heating at 230 C. for an hour. A small excess, say 290 parts, of diethylene glycol mono-butyl ether is added and the mixture refluxed in an apparatus fitted with a fractionating reflux col-,- umn, devised to remove the waters rapidly as possible as it is formed, byheating to about 220 to 250 C. until the reaction is complete,'or for about four hours. The product is a highly viscous liquid readily soluble in most organic solvents.

Example II Rosin, 2000 parts (combiningweight as acid, 340) and maleic anhydride, 575 parts, are heated together at 170 C. for two and a half hours to effect complete condensation. Then 895 parts of glycerol are added and heated at 195-200 C. with efficient agitation for thirty minutes to yield I a very hard brittle resin, solutions of which, in

inert solvents, have excellent demulsifying properties. It dissolves suitable in aromatic solventopropyl alcohol blends.

Example In Methyl abietate, 680 parts, and maleic anhydride, 214 parts, are condensed together by heating at 230 C. for an hour. Glycerol, 134 parts, is added and the mixture heated, under thorough stirring, at 195 C. for an hour and then at 230 C. for an hour. This yields a fairly hard resinous material which dissolves suitable in arcmatic solvent-isopropyl alcohol blends.

Example IV Example V Amyl abietate, 3'72 parts, and maleic anhydride, 98 parts, are heated together for two hours at 215 C. to efiect condensation. Glycerol, 91

parts, is added and the mixture heated at 225 C. for two hours to yield a hard resinous body .which dissolves suitable in isopropyl alcoholaromatic solvent blends. v

Example VI Methyl abietate, 316 parts, and maleic anhydride, 98 parts, are condensed together by heating at 230 C. for an hour. Ethylene glycol, 62

, water softeners, modified fatty acids, oil soluble or water soluble petroleumv sulfonic acids and various other well known demulsiflers for waterin-oil emulsions. The mixtures and proportions of the chemicals which yield the most economical treatment will vary with the various emulsions to be treated. One may add any suitable inert solvent or solvents which would lower the viscosity of the product and so make it more adaptable for use.

In practicing the present invention, a treating agent or demulsifylng agent of the kind above described may be brought into contact with the emulsion to be treated in any of the numerous ways now employed in the treatment of petroleum emulsions of the water-in-oil type with chemical demulsifying agents, such as, for example, by introducing the treating agent into the well in which the emulsion is produced, introducing the treating agent into a tank in which the emulsion is stored, or introducing the treating agent into a container that holds a sludge obtained from the bottom of an oil storage tank. In some instances, it may be advisable to introduce the treating agentinto a producing well in such a way that it will become mixed with water and oil that are emerging from the surrounding strata, before said water and oil enter the barrel of the well Pump or the tubing up through which said water and oil flow to the surface of the ground. After;

temperature varying from atmospheric temperature to about 200 F., so as to-permit the water or brine to separate from the oil, it being preferable to keep the temperature low enough so as to prevent the valuable constituents of the oil from volatilizing. If desired, the treated emulsion may be acted upon by one or the other of various kinds of apparatus now used in the operation of breaking petroleum emulsions, such as homogenizers, hay tanks, gun barrels, filters, ce trifuges, or electrical dehydrators.

The amount of treating agent on the anhydrous basis that is required to break the emulsion may vary from approximately 1 part of the treating agent to 500 parts of emulsionup to 1 part of treating agent to 30,000 parts of emulsion depending upon the type or kind of emulsion being treated. In treating exceptionally refractory emulsions of the kind commonly referred to as "tank bottoms or residual pit oils, the maxi- 2o mum ratio above referred to may be required, but in treating fresh emulsions, i. e., emulsions that will yield readily to the action of chemical demulsifying agents, the minimum ratio mentioned may frequently be satisfactory. For the average petroleum emulsion of the water-in-oil type a ratio of 1 part of treating agent to 10,000 parts of emulsion will usually be found to produce commercially satisfactory results.

It is, of course, understood that some experiment will be required in order to select the precise agent of the aforedescribed group which should be employed for any given emulsionand the quantity in which it is to be employed. As is well known, emulsions vary from'well to well and from time to time in any given well, so that it is quite impossible to lay down any general rule which will be applicable to all emulsions which may be encountered. In order to give some indication, however, of the utility of the agents produced according to the present invention, in the treatment of emulsions, the following specific cases are given. The tests hereinafter described were carried out in laboratory glassware under conditions similar to those which generally exist in the field in treating petroleum emulsions:

A crude petroleum emulsion (from the Humble Gail #53 well on the John Gaillard lease in the Goose Creek, Texas, field) which contained 68% of salt water, was caused to separate into three layers in a few minutes at 125 F. by the addition of a small amount of solution containing four hundredths of one percent (based on the amount of emulsion treated) of material prepared as described in Example II, mixing well and allowin tostand. The top layer contained practically all of the oil almost entirelyfr ee from water. The middle layer which was quite-thin compared to the other two layers contained mineral oil, water, and the added substance. The bottom layer contained practically all of the salt water free from oil.

Under the same conditions this emulsion remained practically unchanged for many hours free of salt water and the lower layer was composed of salt water practically free of oil.

Even several times the amount of the oil soluble sodium salts of petroleum sulfonic acids which 5 in the above case was added, if applied alone under the same conditions, has no appreciable effect in breaking this emulsion.

The same emulsion was caused to separate almost completely within 30 minutes at 125 F. 19 into two layers, the upper layer being oil, nearly free of salt water, and the lower layer being salt water, nearly free of oil, by adding a small amount of solution containing 1 part of material prepared as described in Example III to 5,000 parts of emulsion, mixing well, and allowing to stand.

This same emulsion was broken and caused to separate into layers of oil, practically free of salt water, and of salt water, practically free of oil, within minutes at 125 F. by adding a small amount of solution containing 1 part of material prepared as described in Example III and 1 part of .oil soluble salts of petroleum sulfonic acids to 10,000 parts of emulsion, mixing well and allow- 25 ing to stand.

The present invention having been thus de-' scribed, what is claimed as new and useful and is desired to besecured by Letters Patent is:

l. A process for breaking petroleum emulsions of the water-in-oil type which comprises subjecting the emulsion to the action of. a monohydric alcohol ester derivative of a product obtained by condensing according to the Diels-Alder reaction an aliphatic ether-alcohol ester of a resin acid body with an organic unsaturated carbonyl compound operative'in a Diels-Alder synthesis.

2. A process for breaking petroleum emulsions of the water-i'n-oil type which comprises subjecting the emulsion to the action of a monohydric alcohol ester derivative of a product obtained by condensing according to the Diels-Alder reaction an aliphatic ether-alcohol ester of a resin acid body with a polycarboxylic unsaturated open chain acid body operative in a Diels-Alder synthesis.

3. A process for breaking petroleum emulsions of the water-in-oil type which comprises subjecting the emulsion to the action of a monosynthesis. 4. A process for breaking petroleum emulsions of the water-in-oil type which comprises subjecting the emulsion to the action of a demulsifying agent comprising a monohydric aliphatic alcohol ester derivative of an acidic resin, the

monohydric alcohofresidue or residues each being characterized 'aving fewer than six carbon atoms, the ad ic resin being derived by a Diels-Alder condensation of an aliphatic etheralcohol ester of abietic acid with maleic anhydride, the aliphatic ether-alcohol residue so combined being characterized by having at least one etheric oxygen atom for each six carbon atoms.

of the water-inoil type which comprises subjecting the emulsion to the action of a polyhydric alcohol ester of a product obtained by condensing according to the Diels-Alder reaction a monohydric ether-alcohol ester of a resin acid with 5. A process for breaking petroleum emulsions body operative in a'Diels -Alder synthesis.

6. A process for breaking petroleum. emulsions of the water-in-oil type which comprises sub- Jecting the emulsion to the action of a polyhydric alcohol ester of a product obtained by condensing according to the Dials-Alder reaction a mono- .hydric ether-alcohol ester of a resin acid with a maleic acid body.

'7. A process for breaking petroleum emulsions of the water-in-oil type which comprises subjecting the emulsion to the action of a polyhydric alcohol ester of a product obtained by condensing according to the Diels-Alder reaction a mono-- hydric ether-alcohol ester of abietic acid with a polycarboxylic unsaturated open chain acid body operative in a Dials-Alder synthesis.

8. A process for breaking petroleum emulsions of the water-in-oil type which comprises subjecting the emulsion to the action of a demulsifying agent comprising the reaction product of a polyhydric alcohol and the polybasic acid body formed by a Diels-Alder condensation of a monohydric aliphatic ether-alcohol ester of abietic acid with maleic anhydride, the monohydric aliphatic ether-alcohol residue so combined being characterized by having at least one etheric oxygen 'atom for each six carbon atoms in the monohydric ether-alcohol residue.

a polycarboxylic unsaturated open chain acid 9. A process for breaking petroleum emulsions of the water-in-oil type which comprises subjecting the emulsion to the action of a demulsii'ying agent comprising a polyhyclric alcohol derivative ofthe polybasic acid body formed by a Diels- Alder condensation ofv butyl carbitol abietate with maleic anhydride.

10. A demulsifying agent for petroleum emulsions of the water-in-oil type comprising an ester of a product obtained by condensing according to the Dlels-Alder reaction, an aliphatic etheralcohol ester of a resin-acid body with a carboxylic unsaturated open-chain acid body operative in a Diels-Alder synthesis.

11. A demulsifying agent according to claim 10 in which the ester is a monohydric alcohol ester.

12. A demulsifying agent according to claim 10 in which the ester is a polyhydric alcohol ester. 13. A demulsifying agent according to claim 10 in which the ether-alcohol is butyl carbitol.

14. A 'demulsifying agent for petroleum emulsions of the water-in-oil type comprising a polyhydric alcohol derivative of a polybasic acid body formed by a Diels-Alder condensation of butyl carbitol abietate with maleic anhydride.

. RICHARD A. SALATHIEL. 

